Alpine spilites were thought to have a primary origin for two main reasons. They occur in regions which were considered at one time to lie outside the domain of Alpine regional metamorphism, and they exhibited fresh primary textures of volcanic rocks. These two criteria have been invalidated; regional metamorphism in the Alps is much more extensive than was thought and some fresh-looking spilitic rocks have been demonstrated to develop from basaltic andesites in the laumontite and the prehnite-pumpellyite facies. Spilitic assemblages have been looked for in vain in rather shallow continental non-orogenic pillow lavas. The rare spilites dredged from the bottom of the ocean have been interpreted as resulting from the metamorphism under a pile of lava flows of normal basalts (CANN, 1969). The idea of primary (sensu lato) spilites should not yet be discarded. One can conceive that magma intruding into soft uncompacted sediment full of water could consolidate into a rock remaining hot long enough in the presence of water to undergo conditions similar to those of light burial metamorphism.